What is fluoxetine?

Fluoxetine is a selective serotonin reuptake inhibitors (SSRI) antidepressant. Fluoxetine affects chemicals in the brain that may become unbalanced and cause depression, panic, anxiety, or obsessive-compulsive symptoms.

Fluoxetine is sometimes used together with another medication called olanzapine (Zyprexa). to treat depression caused by bipolar disorder (manic depression). This combination is also used to treat depression after at least 2 other medications have been tried without successful treatment of symptoms.

Fluoxetine may also be used for purposes not listed in this medication guide.

What is the most important information I should know about fluoxetine?

You should not use fluoxetine if you also take pimozide or thioridazine, or if you are being treated with methylene blue injection.

Do not use fluoxetine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine. You must wait at least 14 days after stopping an MAO inhibitor before you can take fluoxetine. You must wait 5 weeks after stopping fluoxetine before you can take thioridazine or an MAOI.

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Some young people have thoughts about suicide when first taking an antidepressant. Your doctor will need to check your progress at regular visits while you are using fluoxetine. Your family or other caregivers should also be alert to changes in your mood or symptoms.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.

If you also take olanzapine (Zyprexa), read the Zyprexa medication guide and all patient warnings and instructions provided with that medication.

What should I discuss with my healthcare provider before taking fluoxetine?

Do not use fluoxetine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine. You must wait at least 14 days after stopping an MAO inhibitor before you can take fluoxetine. You must wait 5 weeks after stopping fluoxetine before you can take thioridazine or an MAOI.

You should not use fluoxetine if you are allergic to it, if you also take pimozide or thioridazine, or if you are being treated with methylene blue injection.

If you also take olanzapine (Zyprexa), read the Zyprexa medication guide and all patient warnings and instructions provided with that medication.

To make sure fluoxetine is safe for you, tell your doctor if you have:

cirrhosis of the liver;

kidney disease;

diabetes;

narrow-angle glaucoma;

seizures or epilepsy;

bipolar disorder (manic depression);

a history of drug abuse or suicidal thoughts; or

if you are being treated with electroconvulsive therapy (ECT).

Some young people have thoughts about suicide when first taking an antidepressant. Your doctor will need to check your progress at regular visits while you are using fluoxetine. Your family or other caregivers should also be alert to changes in your mood or symptoms.

FDA pregnancy category C. Taking an SSRI antidepressant during pregnancy may cause serious lung problems or other complications in the baby. However, you may have a relapse of depression if you stop taking your antidepressant. Tell your doctor right away if you become pregnant while taking fluoxetine. Do not start or stop taking this medicine during pregnancy without your doctor's advice.

Fluoxetine can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Do not give this medication to anyone under 18 years old without medical advice.

How should I take fluoxetine?

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Do not crush, chew, break, or open a delayed-release capsule. Swallow it whole.

Measure liquid medicine with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

It may take up to 4 weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.

Do not stop using fluoxetine suddenly, or you could have unpleasant withdrawal symptoms. Ask your doctor how to safely stop using fluoxetine.

To treat premenstrual dysphoric disorder, the usual dose of fluoxetine is once daily while you are having your period, or 14 days before you expect your period to start. Follow your doctor's instructions.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

If you miss a dose of Prozac Weekly, take the missed dose as soon as you remember and take the next dose 7 days later. However, if it is almost time for the next regularly scheduled weekly dose, skip the missed dose and take the next one as directed. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking fluoxetine?

Drinking alcohol can increase certain side effects of fluoxetine.

Ask your doctor before taking a nonsteroidal anti-inflammatory drug (NSAID) for pain, arthritis, fever, or swelling. This includes aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib (Celebrex), diclofenac, indomethacin, meloxicam, and others. Using an NSAID with fluoxetine may cause you to bruise or bleed easily.

This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Fluoxetine side effects

Get emergency medical help if you have any of these signs of an allergic reaction: skin rash or hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.

severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common side effects may include:

sleep problems (insomnia), strange dreams;

headache, dizziness, vision changes;

tremors or shaking, feeling anxious or nervous;

pain, weakness, yawning, tired feeling;

upset stomach, loss of appetite, nausea, vomiting, diarrhea;

dry mouth, sweating, hot flashes;

changes in weight or appetite;

stuffy nose, sinus pain, sore throat, flu symptoms; or

decreased sex drive, impotence, or difficulty having an orgasm.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Fluoxetine dosing information

Usual Adult Dose for Bulimia:

Immediate-release oral formulations:Recommended dose: 60 mg orally once a day

Comments:-Some patients may need to be started at a lower dose and titrated up over several days to the recommended dose-Daily doses greater than 60 mg have not been systematically studied for the treatment of Bulimia

Use: Acute and maintenance treatment of binge-eating and vomiting behaviors in moderate to severe Bulimia Nervosa.

Comments:-Doses above 20 mg per day may be given in divided doses, in the morning and at noon-The full effect may be delayed until after at least 4 weeks of treatment -If a satisfactory response with the once weekly oral fluoxetine is not maintained, a change back to daily fluoxetine dosing using the immediate-release oral formulations should be considered.-Acute episodes of Major Depressive Disorder require several months or longer of sustained pharmacologic therapy-Whether the dose needed to induce remission is the same as the dose needed to maintain and/or sustain euthymia is unknown

Use: Acute and maintenance treatment of Major Depressive Disorder (MDD)

Comments:-Doses above 20 mg per day may be given in divided doses, in the morning and at noon-The full effect may be delayed until after at least 5 weeks of treatment

Use: Acute and maintenance treatment of obsessions and compulsions in patients with Obsessive Compulsive Disorder (OCD)

Usual Adult Dose for Panic Disorder:

Immediate-release oral formulations:Initial dose: 10 mg orally once a day, increased after one week to 20 mg orally once a dayMaintenance dose: 20 to 60 mg orally per dayMaximum dose: 60 mg orally per day

Comments:-Doses above 20 mg per day may be given in divided doses, in the morning and at noon-A dose increase may be considered after several weeks if no clinical improvement is observed.-Doses greater than 60 mg per day have not been systematically studied for the treatment of Panic Disorder

Use: Acute treatment of Panic Disorder

Usual Adult Dose for Premenstrual Dysphoric Disorder:

Immediate-release oral formulations:Initial dose: Continuous regimen: 20 mg orally once a day on every day of the menstrual cycleCyclic regimen: 20 mg orally once a day starting 14 days prior to the anticipated start of menstruation through to the first full day of menses, and repeated with each new cycle

Maintenance dose: 20 to 60 mg per day for either the continuous or intermittent regimensMaximum dose: 80 mg orally per day

Duration: The 20 mg daily dosage has been shown to be effective for up to 6 months of treatment

Comments:-A daily dose of 60 mg has not been shown to be significantly more effective than 20 mg daily-Daily doses above 60 mg have not been systematically studied in patients with this condition

Usual Pediatric Dose for Depression:

Immediate-release oral formulations:8 to 18 years:Initial dose: 10 to 20 mg orally once a day; the 10 mg daily dose may be increased after one week to 20 mg orally once a day

Lower weight children:Initial dose: 10 mg orally once a day, increased to 20 mg orally once a day after several weeks if insufficient clinical improvement is observed

Maintenance dose: 10 to 20 mg orally once a day

Comments:-The full effect may be delayed until after at least 4 weeks of treatment-The potential risks versus clinical need should be assessed prior to using this drug in children and adolescents

Use: Acute and maintenance treatment of Major Depressive Disorder (MDD)

Usual Pediatric Dose for Obsessive Compulsive Disorder:

7 to 18 years:Immediate-release oral formulations:Adolescents and higher weight children:Initial dose: 10 mg orally once a day, increased to 20 mg orally once a day after 2 weeksMaintenance dose: 20 to 60 mg orally per dayMaximum dose: 60 mg orally per day

Lower weight children:Initial dose: 10 mg orally once a day, increased after several weeks if insufficient clinical improvement is observedMaintenance dose: 20 to 30 mg orally once a dayMaximum dose: 60 mg orally per day

Comments:-Additional dose increases may be considered after several more weeks if clinical improvement is insufficient-Doses above 20 mg per day may be given in divided doses, in the morning and at noon-In lower weight children, there is minimal experience with doses greater than 20 mg per day, and none with doses greater than 60 mg per day-The full effect may be delayed until after at least 5 weeks of treatment-The potential risks versus clinical need should be assessed prior to using this drug in children and adolescents

Use: Acute and maintenance treatment of obsessions and compulsions in patients with Obsessive Compulsive Disorder

What other drugs will affect fluoxetine?

Taking this medicine with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking fluoxetine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Many drugs can interact with fluoxetine. Not all possible interactions are listed here. Tell your doctor about all your medications and any you start or stop using during treatment with fluoxetine, especially:

This list is not complete and many other drugs can interact with fluoxetine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Where can I get more information?

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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